• Korean Journal of Radiology
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• v.22 no.4
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• pp.624-633
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• 2021

Objective: To evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters. Materials and Methods: A phantom, simulating the L2-4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings. Results: The skeletal muscle area (threshold, -29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30-150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0-44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used. Conclusion: Measurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.

• 한국해양학회지
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• v.27 no.2
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• pp.164-172
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• 1992

This study was carried out to investigate the benthic polchaete community in the southern area of Kyeonggi Bay, Korea. The species composition was examined in Asan Bay in 1985, the coastal area near Yibug in 1987, the area between Daeranjido and Asan Bay for 1988-1989, and the offshore south of Deogjeogdo in 1992. Polychaetes, the dominant faunal group occupying 57.4% in total density, comprised a total of 124 species with a mean density of 211 indiv.m/SUP -2/. The dominant polychaete was Prionospio sp. (28.8%), followed by Nephtys polybranchia (6.0%), Tharyx sp. (4.8%) Stermaspis scutata (4.4%), Lumbrineris longifolia (3.9%). The Number of species and density were higher in the coastal area near Yibug, Asan Bay and the mouth of Namyang Bay, while lower in the channels of offshore region. The cluster analysis revealed that the study area could be divided into 5 regions, which were distributed serially along the coast from Asan Bay to open sea. Each region sustained its specific Bay, Stermaspis-Heteromastus assemblage from Asan Bay to Daeranjido, Hemipodus assemblage in the channels of offshore, Lumbrineris assemblage on the coastal area o Yibug and Prionospio assemblage in the coastal area south of Yibug. Tharyx-Chone assemblage had the highest species number of 75 spp. and Prionospio assemblage had the highest density of 3,695 indiv.m/SUP -2/ due to the predominance of prionospio sp.. Hemipodus assemblage with the lowest density occupied the largest area in offshore region. The southern Kyeonggi Bay showed higher species number and lower density than the northern Kyeonggi Bay. But the dominant Polychaetes were similar between the southern Bay and the channel regions of the northern Bay.

• Journal of Environmental Impact Assessment
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• v.4 no.1
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• pp.47-57
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• 1995

This study analyzes the problems of environmental laws, development planning laws, Metropolitan Area Development Planning(MADP), and the level of environmental pollution at Pusan and Asan-Bay Metropolitan Area where MADP will be realized in the near future. In order to prevent the environmental pollution by realization of MADP, Environmental Impact Assessment Act and environmental impact assessment systems in Korea should be revised so as to reflect the followings. First, the impact of national landuse planning change on the environment should be considered at the beginning of environmental impact assessment procedures. Second, the overlapping and greater impact of many projects, whose part is the subject of environmental impact assessment, upon surrounding metropolitan area should be simultaneously evaluated and the environmental pollution protection and abatement alternatives must be made according to the above impact of the projects. Thirdly, total effluent regulation of water pollution, air pollution and solid wastes should be enforced based on the self-purification of the metropolitan area environment.

• Journal of Environmental Health Sciences
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• v.42 no.1
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• pp.1-9
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• 2016

Objectives: Personal exposure to air pollution is affected by contact over time and by location. The purpose of this study was to determine the relationship between personal exposure to $PM_{2.5}$ and the time-activity patterns of the elderly in urban and rural areas. Methods: A total of 44 elderly participants were recruited for a 24-hour $PM_{2.5}$ personal exposure measurement. Twenty-four were from Seoul (urban area) and 20 were from Asan (rural area). Energy expenditure and spatiotemporal positioning were monitored through $PM_{2.5}$ measurement. Spearman correlation analysis was conducted to determine the relationship between $PM_{2.5}$ and time-activity pattern. Results: Daily average $PM_{2.5}$ personal exposures were $19.1{\pm}9.7{\mu}g/m^3$ in Seoul and $29.1{\pm}16.9{\mu}g/m^3$ in Asan. Although outdoor exposure was higher in Seoul than in Asan, residential indoor exposure was higher in Asan than in Seoul. Higher $PM_{2.5}$ personal exposure in Asan could be explained by longer time in residential indoor environments and higher indoor $PM_{2.5}$ concentrations. Seoul elderly had higher energy expenditure, which may be due to the use of mass transportation. Conclusion: Personal exposure to $PM_{2.5}$ was higher among Asan elderly than Seoul elderly because of high residential indoor concentrations and longer residential time. Lack of energy spent and higher personal exposure to $PM_{2.5}$ might have led to higher risk among the Asan elderly.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.6
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• pp.70-78
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• 1998

The changes of tidal characteristics of Kyonggi-Bay Region after the Large Reclamations in the Inchon Coastal Area have been studied by the numerical modelling. The constructions of Inchon International Airport and Sihwa Seadike were considered as the main reclaimation projects in this region. A two dimensional hydrodynamic model was used for this study, and it was composed in relatively high resolution with curvilinear orthogonal coordinate. As the results, at the Inchon harbor and Palmido, where a deep channel is developed, the semi tidal ranges(Z$_0$) were decreased in 8 cm after the two reclamations. However, the Z$_0$ values in the outside of the deep channel were decreased only in 2~4 cm, so that the tidal changes in the deep channel were greater than in the outside of it. After the reclamations, the maxmum velocity was increased 17% at the Inchon harbor, however it was decreased from 1. 55 m/s to 1.10 m/s at the Palmido. This is because the available area in which the stream may spread out was largely reduced after the reclamations. An Asan-bay region, the Z$_0$ was decreased in 5 cm at the Punyang-man and Asan-man stations located after the reclamations in Inchon coastal area. However the changes of Z$_0$ were very little at the outside of Asan-bay. In Asan-bay, the current velocity and direction were little influenced by the reclamations in Inchon coastal area.

• Korean Journal of Head & Neck Oncology
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• v.18 no.1
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• pp.30-35
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• 2002

Objective: To determine the effectiveness and toxicity of chemoradiation therapy in nasopharyngeal carcinoma by comparing with radiation therapy alone. Materials and Methods: Between October 1989 and July 2000, One hundred eleven patients with newly diagnosed and histologically proven nasopharyngeal carcinoma treated in Department of Radiation Oncology, Asan Medical Center were retrospectively reviewed. Forty-five patients were treated with radiation therapy alone (Group I) and 66 patients were treated with radiation therapy and concurrent cisplatin (Group II). Cisplatin was administered once a week, on the first day of each successive week of treatment, starting on day 1 of radiation therapy and given as a intravenous bolus at a dose of $20mg/m^2$ of body-surface area. Radiation therapy was given in doses of 1.8Gy, once a day, 5 days per week with 4MV or 6 MV photons. Initial field was received a total of 60Gy and a primary tumor and enlarged lymph nodes were boosted with an high dose intracavitory brachytherapy and 3D conformal therapy. Results: The complete response rate was 86.7% in Group I, and was 90.9% in Group II. The 5 year overall survival rate for Group I was 60% and for Group II was 45% (p=0.2520). The 5 year disease free survival rate was 52% versus 45%, respectively (p=0.7507). The median follow up was 44 months versus 34 months, respectively. Conclusion: Analysis of the III patients showed no significant difference in disease free survival and overall survival in two treatment group. This retrospective analysis did not demonstrate benefit with concurrent chemoradiation using cisplatin at a dose of $20mg/m^2$ of body-surface area in treatment result than radiation alone.

• Journal of Environmental Impact Assessment
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• v.4 no.3
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• pp.63-71
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• 1995

This study analyzes the problems of environmental laws, development planning laws, Metropolitan Area Development Planning (MADP), and the level of environmental pollution at Asan-bay metropolitan area, where MADP will be realized in the near future. In order to prevent environmental pollution by the implementation of MADP, the Environmental Impact Assessment (EIA) Act and EIA systems in Korea should be revised so as to reflect the followings. First, the impact of national landuse planning changes on the environment should be considered at the beginning of the EIA procedures. Second, the overlapping and greater impact of many projects upon surrounding metropolitan areas should be simultaneously evaluated, though each project is the subject of EIA, and the environmental pollution protection and abatement alternatives must be made in accordance with the above impact of the projects. Thirdly, total effluent regulation of water pollution, air pollution and solid wastes should be enforced based on the self-purification of the metropolitan area environment.

• Clinical and Experimental Pediatrics
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• v.59 no.sup1
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• pp.139-144
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• 2016

Encephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous syndrome that affects ectomesodermal tissues (skin, eyes, adipose tissue, and brain). The neurologic manifestations associated with ECCL are various including seizures. However, ECCL patients very rarely develop brain tumors that originate from the neuroepithelium. This is the first described case of ECCL in combination with dysembryoplastic neuroepithelial tumor (DNET) that presented with intractable seizures. A 7-year-old girl was admitted to our center because of ECCL and associated uncontrolled seizures. She was born with right anophthalmia and lipomatosis in the right temporal area and endured right temporal lipoma excision at 3 years of age. Seizures began when she was 3 years old, but did not respond to multiple antiepileptic drugs. Brain magnetic resonance (MR) imaging performed at 8 and 10 years of age revealed an interval increase of multifocal hyperintense lesions in the basal ganglia, thalamus, cerebellum, periventricular white matter, and, especially, the right temporal area. A nodular mass near the right hippocampus demonstrated the absence of N-acetylaspartate decrease on brain MR spectroscopy and mildly increased methionine uptake on brain positron emission tomography, suggesting low-grade tumor. Twenty-four-hour video electroencephalographic monitoring also indicated seizures originating from the right temporal area. Right temporal lobectomy was performed without complications, and the nodular lesion was pathologically identified as DNET. The patient has been seizure-free for 14 months since surgery. Although ECCL-associated brain tumors are very rare, careful follow-up imaging and surgical resection is recommended for patients with intractable seizures.

• Archives of Reconstructive Microsurgery
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• v.11 no.2
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• pp.162-166
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• 2002

The anterolateral thigh free flap was first reported by Song et al. in 1984 as a fasciocutaneous flap based on septocutaneous or musculocutaneous perforators of the lateral femoral circumflex vessel. It only becomes popular recently through confirmation of additional anatomy. For reconstruction of Achilles area defect, a thin flap is required to improve aesthetic and functional results. The anterolateral thigh free flap is relatively thin and can provide large skin area. It can be a useful option for reconstruction of Achilles area defect based on these characters. Since March 2002, we have successfully transferred 4 anterolateral thigh free flaps to reconstruct Achilles area defects and have attained good range of motion in this region. The anterolateral thigh free flap has many advantages and can be used for the reconstruction of Achilles tendon area defect.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.183-188
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• 2005

Defect on the temporal area caused by, surgical ablation of a tumor or an infection should be reconstructed immediately to prevent potentially life-threatening complications such as meningitis and cerebrospinal fluid leakage. The defect on the temporal area usually presents as a typical 'cone-shape'. Successful reconstruction requires sufficient volume of well-vascularized soft tissue to cover the exposed bone and dura. From 1994 through 2003, the authors applied rectus abdominis free flap for the reconstruction of the temporal defect from 1994 through 2003. There were 10 patients with a mean age of 52.1 years. Of these 10 patients, external auditory canal cancer was present in four patients, temporal bone cancer in two, parotid gland cancer in one and three patients were reconstructed after debridement of infection(destructive chronic otitis media). All the free flaps survived, and flap-related complications did not occur. Compared to a local flap, the rectus abdominis free flap can provide sufficient volume of well-vascularized tissue to cover the large defect and can be well-tolerated during an adjuvant radiation therapy. The long and flat muscle can be easily molded to fit in to the 'cone-shape' temporal defect without dead space. It is also preferred because of the low donor site morbidity, a large skin island and an excellent vascular pedicle. Two-team approach without position change is possible. In conclusion, the authors think that rectus abdominis free flap should be considered as one of the most useful method for the reconstruction of a cone-shaped temporal defect.